Improvement in steam-engines



To all whom it nia/y concern: I l 2 Be it known that I, JOHN S. BARDEN, of Provi- Island, have invented certain Improvements in Steam- 1 lEngines; and I do hereby declare the following to be l `accompanying drawing and letters of reference marked 4thereon, which drawing represeuts'a vertical section4 embodying my invention.

the passage of the crank over the" dead centers, thus making the steam-engine more eiicient and regular in l transversely to the direction of motion of the irst piswith a double-armed level-,the fulcrumot' which being the rst piston, the second piston is set in motion, carrying the short arm of the lever with it, while the other barrel, air and valve-chambers, one casting, a stratum ,between the steam and water apartments to prevent l a too rapid condensation of the steam, also extending t e, and forms there a piston for the latter.

, piston d, the long arm, g, being attached to the crank-` pin of crank h.

and ,sara

` JOHN-s. Barman, or rnovinnivon, RHODE ISLAND,

Leef/rs Parmi No; 100,841, daad Mmh 15, 1870.

IMPRQvEMENT INsTEAM-ENGINES,

The Schedule referred to in these Letters Patent and making part of the same.

dence, in the county of lProvidence, and State of Rhode.

a fnll, clear, and exact description of the construction and operation of the same, reference being had to the ofsteam-cylinder with piston, steam-valves, crank, &c.,

The object of my invention is to avoidthe loss of steam and power in reciprocating steam-engines by its motion.

My invention consists in a piston provided with a cylindrical cavity, within which aseeond piston moves ton.

It further Vconsists 'in connecting the4 second piston attached4 to and moving with the first piston in such manner that when the crank approaches one of the dead centers, bythe admission of steam into the cavi-ty of arm throws the crank over the dead center.

It further consists in` anautomaticvalve arrangement, by which, through the motion ofthe irstpiston, steam is admitted'into they cavity for propelling the second piston and exhausted therefrom. i v

'Italso consists in so connecting a pump with the Vsteam-cylinder that the latter forms,`with the pumpof non-conducting material like zinc being interposed a portion ofthe tirst piston or piston-rod of the steam cylinder in the pump-barreh'thus producing asteampump of great simplicity and at little cost.

In the drawings- 1 i `ais the inside of the steam-cylinder, with piston b, cavity c, and second piston d.

, `rlphe piston b is provided with cylindrical projections, the upperone ot which extends through the pistonhead, acting as in ordinary trunk-engines. The lower one, which mayfbe solid, passesinto the pump-barrel Within the upper cylindrical projection isattached the fulcrum' of a double-arm lever, of which the shorter amtl f, extends into a cavity provided for it ,in4V the Thesteam-alve iis att-ached, operated, and ar- `steam-cylinder, 85e.

ranged inthe usual manner, and at the opposite side of the cylinder is anotherl steam-chest, in which, operates the automatic valve k, for admitting steaminto the cavity of piston b, which latter, when nearly completing its upward stroke, comes in contact with the projection n of valve k, and thus raises the latter and opens steam communication through port 0 and passage p, in the cavity of piston b.

The steam now propels pistou d, and with it the portions f and g ot' lever and crank h, over the dead centen The piston d, when near port o, has opened the aperture u, thus allowing the steam at that'portion of the cavity to exhaust into the cylinder a., and from there into the exhaust of the latter. After the piston el has started and covered'again the aperture u, there maybe some steam left in that portion of the cavity, but of too small density and force to resist effectually the action of live steam on the other side of piston d;

The piston b, at the down-stroke, acts against the projection n of valve k, moving the latter and establishing steam communication between the further end of cavity and valve k, by means of port fr and passage g, while the steam on the opposite side of piston d exhausts through aperture tinto the lower portion of It will be observed that the double-arm lever is placed within an open cylindrical projection of piston b, thus allowing the air to circulate in and around the moving parts of the lever, and pre venting friction om undue expansion of the working parts.`

\ Having thus fully described my invention,

Vhat I claim as new, and desire to secure by Letters Patent, is-

l. 'lhe combination of hollow piston d, in the manner and for the described.

l 2. The pistons b and cl in combination with vibrating lever and crank 1:,in the manner and for the-purpose specified.

`3. The cylinder a and piston b, in combination with piston d,'valves 'i and k, steam-inlets o lr, and exhaustb with piston purpose substantially as 'ports u t, in the manner and for the purpose set forth.

. 4l The steam-cylinder a, in combination with pumpbarrel a, stratum of non-conducting material y, constructed in the manner and forl the purpose as above described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. i I 

